io_uring: use call_rcu_hurry if signaling an eventfd

io_uring uses call_rcu in the case it needs to signal an eventfd as a
result of an eventfd signal, since recursing eventfd signals are not
allowed. This should be calling the new call_rcu_hurry API to not delay
the signal.

Signed-off-by: Dylan Yudaken <dylany@meta.com>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Link: https://lore.kernel.org/r/20221215184138.795576-1-dylany@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 4601e48a173d10ef6a265b309c94db09a2f5278b..16a323a9ff70d758b9c8d9faaebfef189083dad1 100644 (file)
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -538,7 +538,7 @@ static void io_eventfd_signal(struct io_ring_ctx *ctx)
        } else {
                atomic_inc(&ev_fd->refs);
                if (!atomic_fetch_or(BIT(IO_EVENTFD_OP_SIGNAL_BIT), &ev_fd->ops))
-                       call_rcu(&ev_fd->rcu, io_eventfd_ops);
+                       call_rcu_hurry(&ev_fd->rcu, io_eventfd_ops);
                else
                        atomic_dec(&ev_fd->refs);
        }